14 Settle it therefore in your hearts, not to meditate before what ye shall answer: 15 For I will give you a mouth and wisdom, which all your adversaries shall not be able to gainsay nor resist. Luke 21:14-15
This portion of scripture is speaking about the end times. Jesus tells the disciples not to fret and worry about what they will say if questioned or arrested (my take) by the “authorities”. God will put words in their mouths so the adversaries (from the Greek to lie opposite, be adverse) will not be able to gainsay (from the Greek to refute or deny) nor resist (from the Greek to stand against).
It is no different today; we are closer to the end times than the disciples. Now more than ever we need to put our trust in God and not be afraid of men. God will protect and guide us in everything, even the words we speak.
We need to trust God and “be not afraid”. … because greater is He that is in you than he that is in the world. I John 4:4